Uterine leiomyomata (UL), or fibroids, are a major source of gynecologic morbidity among reproductive aged women and account for 2.1 billion dollars in health care costs each year in the United States. Black women are 2-3 times more likely than white women to be diagnosed with UL and they have more severe disease at the time of diagnosis. Known risk factors for UL do not explain the high incidence among black women. Recent evidence suggests that stress may play an etiologic role in UL development. We propose to assess the role of various psychosocial stressors-abuse victimization, adverse socioeconomic conditions, family caregiver responsibilities, depressive symptoms, and self-reported daily stress-in relation to incident UL diagnosed over 14 years of follow-up (1997-2011) in the Black Women's Health Study (BWHS), a large prospective cohort study of African-American women. We will also examine the role of coping in buffering these effects. To date, only abuse victimization has been assessed in relation to incident UL, in a study of white women. Thus, the proposed study will provide novel data on plausible causes of UL that have been little studied. Since the inception of the BWHS in 1995, participants have been followed biennially by questionnaire, and cohort retention has been high (>80%). Validation studies in the BWHS have demonstrated high accuracy of self-reported UL (>96%) and high reproducibility of various psychosocial measures. During follow-up from 1997-2011, more than 7,500 incident cases of UL will have been diagnosed by ultrasound or surgery. The large number of incident cases will provide excellent statistical power to achieve the study aims and will also allow for informative analyses of subgroups of special interest, such as women under age 35 (N=3,000 cases). The high incidence of UL in black women is a problem of public health importance. Psychosocial factors hypothesized to increase risk (e.g., childhood abuse victimization and socioeconomic adversity) are more prevalent in black women than white women. Thus, the proposed study will assess potential risk factors for UL that are of special relevance to black women. The study can be carried out at low cost because follow-up and data collection are supported by other grants. The identification of modifiable risk factors could yield useful data for primary prevention efforts and potentially have a large impact on the public health burden of disease.